Intergovernmental International Technological Innovation Cooperation under National Key Research and Development Program of China

Project Title: Improved biogas process with enhanced nitrogen recovery for green fertilizer production

Chinese part:University of Science and Technology Beijing (USTB)

Austrian parts: University of Natural Resources and Life Sciences (BOKU), Vienna and Bioenergy 2020+

Chinese Project Manager: Prof. Dr. Zifu Li

Austrian Project Manager: Prof. Dr. Werner Fuchs https://boku.ac.at/ifa-tulln/

Execution Period: December 2016 to December 2018

Project Description:

Worldwide about 170 Mio t (China: 35 Mio t, EU: 20 Mio t, Austria: 0.4 Mio t) of N-rich by-products are annually generated only from cattle, pig and chicken meat processing industry. Manure and waste from animal breeding is another huge source. Both categories represent a high potential for renewable energy and green fertilizer production. The removal of ammonia, an inhibiting agent, from the AD fermentation process, leads to an energy efficient production of biogas and increases biomass conversion rate and methane yield.

A combined process for integrated removal of nitrogen from fermentation broths enables stable anaerobic treatment of N-rich input material in order to generate both, energy in form of methane and added-value “green” N-fertiliser. An innovative membrane technique for integrated nitrogen removal as well as conventional stripping will allow anaerobic mono-digestion of N-rich industrial waste such as chicken manure or slaughterhouse waste in combination with a reasonable recycling of nutrients as organic fertilizer. Nitrogen is recycled as ammonium sulfate or ammonium nitrate, a high-quality and marketable fertilizer which has high potential to replace chemical N-fertilizers and thus to significantly reduce the impact (CO2 footprint, GHG emission) on environment.

This project is leaded by Pro. Zifu Li at University of Science and Technology Beijing and cooperates BIOENERGY 2020+ and University of Natural Resources and Life Sciences (BOKU) in Vienna, Austria. BIOENERGY2020+ Research Centre is an Austrian Research Centre in the field of biomass and bioenergy. The center is organized in biomass combustion systems, biomass gasification systems and bioconversion of waste and renewable resources. Institute for Environmental Biotechnology at BOKU focuses on the exploitation of the microbial metabolism to safeguard the quality of life and preserve natural resources. The project forms an integrated approach for a “zero emission-added value” AD with enhanced productivity and stability and valorisation of all residuals and establishes a stable AD process accepting N-rich substrates (chicken waste, slaughterhouse waste, pig manure) by two nitrogen removal technologies (stripping and membrane contactor). By reducing the ammonia concentration in the reactor, methane producing microorganisms can be less inhibited and high COD removal rates as well as high specific methane yield can be observed. As a result an appropriate treatment technology of problematic N-rich organic waste as well as the provision of “green” N-fertiliser can be expected.